I got the idea, but there is a problem how html mark this part of the code. Here it is
<div lang="en" dir="ltr"><div id="mw-pages">
<h2>Pages in category "English A"</h2>
<p>The following 3 pages are in this category, out of 3 total.
</p><div lang="en" dir="ltr" class="mw-content-ltr"><h3>A</h3>
<ul><li><a href="/index.php/Akon" title="Akon">Akon</a>
This part I need to be displayed:
<ul><li><a href="/index.php/Akon" title="Akon">Akon</a>
So I tried to hide this "mw-pages" using your method and all was hidden including the content that I need to be displayed! So I don't know how to find a solution!